Device for preventing the turning or withdrawal of cylinder locks



P. W. C. DEMENT DEVICE FOR PREVENTING THE TURNING OR WITHDRAWAL OF CYLINDER LOCKS Filed March 21. 1923 HIGHS, 3

Patented July 15, 1924.

entree stares PATENT FFEE PERCY WILLIAM CHARLES DEMENT, OF KILBIRNIE, WELLINGTON, NEW ZEALAND.

DEVICE FUR PREVENTING THE TURNING OR W'ITHDRAWAL OF CYLINDER LOCKS.

Application filed March 21, 1923. Serial No. 626,647.

T all whom it may concern:

Be it known that 1, .Pnnor WILLIAM CHARLES DEMENT, a citizen of the Dominion of New Zealand, residing at 74 Moxham Avenue, Kilbirnie, lVellington, in the Provincial District of Vellington, New Zealand, have invented an Improved Device for Pre venting the Turning or lVithdrawal of Cylinder Locks, of which the following is a specification.

This invention relates to means for preventing unauthorized turning or withdrawal of cylinder locks of the pin tumbler type in, or from doors or other fixtures, in which they may be fitted.

Hitherto locks of the above mentioned type have in some cases been secured in doors and the like against unauthorized turning and withdrawal by means of casings fitted in the doors or the like, and which received the aforesaid locks.

This invention has for its object the securing of said locks against unauthorized turning and withdrawal. without the aid of casings.

According to the invention a plate is in serted in the edge of the door or the like so as to cross the hole made to receive the lock, said plate containing an opening which receives the end of the lock, and also containing recesses in which the lugs of the lock are engaged, on the latter coming to its final position in the door or the like.

An edge of the opening in the plate is at such a level, that when the screws which connect the lock with the latch housing are entered in the lugs ot' the lock, they are in close contact with said edge the result of which is that while said screws are entered in the lugs of the lock, the latter cannot be removed from the recesses, and withdrawal of the lock from the door or the like is prevented.

At the same time owing to the connecting screws being in contact with the edge of the opening in the plate, turning of the lock in the door or the like is also prevented.

Referring to the accompanying drawing in conjunction with which the invention will be further described Figure 1 is a part sectional elevation of a door showing a lock secured therein by the improved device.

Figure 2 is a rear elevation of the parts shown in Figure 1, with the latch housing removed.

Figure 3 is a plan view of the plate.

Figure l an elevation thereof, while Figure 5 shows the edge of the door with the opening made therein to receive the plate.

The plate 1 contains an opening 2, which receives the inner end of the lock 3, the cylinder 01 the latter being accommodated in the lower recess 1 of said opening. I

Lugs 7 one ateach side of the opening 1 extend forwardly and upwardly from the plate 1 so as to provide recesses 8, the latter being purposely formed to receive the lugs 9 of the lock.

The plate 1 is inserted in the edge of the door 10, so as to cross the hollow 11 made therein to receive the lock and so that the inner end of the latter can be inserted in the plate.

In fitting the latter and the lock in the door, a hole 12 is bored in the edge of the door at right angles to and crossing the hole 11 in which the lock is to be inserted, and approximately level with the centre of said hole 11.

Upper and lower saw cuts 13 are made from the hole 12, to provide a slot in which the plate 1 can be inserted, the hole 12, after being enlarged it necessary, permitting the lugs 7 and bulge 14 of the plate 1 to pass into the door 10.

The inner end of the plate 1 is formed with one or more points 15, to enable it to be driven into the wood during the last portion of its insertion in the door. Also said plate 1 has at its outer end a right angle portion 16 with teeth or spikes 17 adapted to be driven into the edge of the door.

YVhen the plate 1 has been driven fully home into the door 10. the opening 2 registers with the hole 11 which receives the lock.

The lock 3 is then inserted in the hole 11 from the outside of the door, and kept raised to enable the lugs 9 of the lock to be dropped down behind the forwardly and upwardly extending lugs 7 of the plate 1 into the re cesses 8. The bulge 14 enables the lock 3 to be inserted far enough to permit the lugs to enter the recesses 8. i

The connecting screws 18 from the latch housing 20 are then screwed into the lugs 9 of the lock and by their contact with the upper edge 2 of the opening 2 prevent said lugs 9 from leaving the recesses 8 and the look from being withdrawn from the hole 11. At the same time the contact of the screws 18 with the upper edge 2 of the opening 2 prevents the lock from bein turned in the hole 11;

When the door is closed access cannot be had to the outer end 16 of the plate 1 on the edge of the door, and in any case the plate 1 cannot be withdrawn until the lock is completely dismantled, and to do this, access must be had to the inside of the door.

The latch bar 19 passes from the cylinder of the lock 3 to thelatch housing 20 as usual.

Vhat I do claim and desire to obtain by Letters Patent of the United States of America 1s 1. Means for securing locks of the kind specified, comprising, a plate insert-able in a door or the like; so as to cross a lock receiving hole in the door, an aperture in the plateso positioned as to register with the hole, and recesses in said plate and adjacent the aperture for receiving and retaining lugs of a lock with which used.

2. Means, according to claim 1, for securing locks of a kind specified, in combination with connecting screws for entering the lugs of the lock, the screws, when in the lugs, making contact with an edge of said aperture, thereby preventing movement of the lugs out of the recesses.

3. Means, according to claim 1, for use in securing locks of the kind specified, said recesses in the plate for receiving the lugs of the lock, being packeted by plate portions extending forwardly and upwardly from said plate.

4. Means. according to claim 1, for use in securing locks of the kind specified, said plate being provided with pointed formations at its inner and outer ends for driving into the woodwork of the door or the like.

A means according to claim 1, said plate having a depressed portion adjacent said aperture, whereby to allow insertion of said lock lugs into said recesses.

PERCY WILLlAM CHARLES DEMENT. 

